Literatura académica sobre el tema "Ostriches"
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Artículos de revistas sobre el tema "Ostriches"
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Honnas, Clifford M., James Jensen, Janyce L. Cornick, Karen Hicks y Bruce S. Kuesis. "Proventriculotomy to relieve foreign body impaction in ostriches". Journal of the American Veterinary Medical Association 199, n.º 4 (15 de agosto de 1991): 461–65. http://dx.doi.org/10.2460/javma.1991.199.04.461.
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Summary A study was conducted to identify the clinical signs associated with impaction of the proventriculus in ostriches, to identify diagnostic aids, and to develop a surgical procedure for management of the disorder. Clinical signs indicating the need for surgical intervention included chronic inappetance, a change in fecal consistency or production, dehydration, weight loss, and failure to respond to laxatives. Diagnosis of impacted proventriculus was by abdominal radiography and external palpation. Impactions were caused by sand and rocks (5 ostriches), hay and sand (1 ostrich), and leaves (1 ostrich). After surgery, 5 of the ostriches were clinically normal within (mean) 1 week. One ostrich failed to regain a normal appetite until 2 weeks after surgery, and one juvenile ostrich died after surgery. Of the 6 ostriches that survived, 1 died 1 week after discharge from the hospital. The remaining birds survived without redevelopment of impaction.
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Paliy, A. P., N. V. Sumakova y R. V. Petrov. "Endoparasic diseases of ostriches in eastern Ukraine". Ukrainian Journal of Ecology 10, n.º 4 (10 de agosto de 2020): 235–41. http://dx.doi.org/10.15421/2020_193.
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In ostrich farming is difficult to obtain the necessary production and economic results without protection of bird health. We determined the incidence of parasitic ostriches during the period of growing and keeping on specialized eco-zoos. Samples from small and large farms, as well as eco-parks in Kharkiv, Dnepr and Donetsk regions of Ukraine, were examined during 2016- 2020. We performed a parasitological study of 159 samples from three species of ostriches (black African ostrich, Australian common Emu (Dromaius), Rhea). Infestation of ostriches of different ages with two types of nematodes and Eimeria was established. We determoined that the population of ostriches in specialized farms and eco-zoos was infested with nematodes and protozoa with an extensiveness of invasion from 7.7% to 71.4% among adult birds, while young ostriches were infested with Emeria from 20.0% to 44.4%. The largest invasion by helminths and protozoa was observed among black African ostriches in Kharkiv region (41.4%), in Dnepr region it was 33.3%, and in Donetsk it reached 34.1%. Among the livestock of ostriches, there were both mono and mixinvasions. Most often, this was an invasion by Trichostrongylus spp. and Eimeria spp. in African black ostriches, capillaries and Eimeria in Emu. In Kharkiv region, the invasion of Capillaria by Trichostrongylus in African ostriches and Trichostrongylus in Emu were found when they were kept together. Acute and chronic eimeriosis disease can lead to the death of ostriches at the age of 3-4 months.
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Engelbrecht, A. y S. W. P. Cloete. "Preliminary investigations into the effect of ostrich feather lice (Struthiolipeurus struthionis) on production and leather quality". Animal Production Science 52, n.º 5 (2012): 347. http://dx.doi.org/10.1071/an11330.
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The effect of ostrich feather lice (Struthiolipeurus struthionis) on productivity and leather quality was investigated in the light of louse-related skin damage on other livestock species that seems similar to defects, called pitting, seen on ostrich skins. The occurrence and spread of feather lice on ostriches were also studied. Natural infestation of louse-free ostriches within a group mixed with louse-infested ostriches was achieved within 6 months. Lousiness was determined by visual counts on the body and feathers of the ostriches on five locations. There was a relatively low correlation between the number of lice observed on the live ostriches and the actual number of lice extracted from harvested wing feathers. However, it was demonstrated that lice obtained from feathers increased at a rate of 3.29 (s.e. = 1.34) lice per 100 g of feathers for an increase of one louse observed on the live birds in the paddock (R2 = 0.23). Treatment with synthetic pyrethroid insecticides eradicated all lice. Louse infestation had no significant influence on growth or slaughter traits, while no causal relationship between louse infestation and pitting damage on the processed ostrich skins could be demonstrated.
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Ščerbová, J. y A. Lauková. "Escherichia coli strains from ostriches and their sensitivity to antimicrobial substances". Polish Journal of Veterinary Sciences 19, n.º 2 (1 de junio de 2016): 415–23. http://dx.doi.org/10.1515/pjvs-2016-0052.
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AbstractOstriches are bred especially for their high-quality meat. There is a lack of knowledge concerning the ostrich’s microflora.Escherichia coliis a commensal microorganism of the poultry intestine, ostriches included. However, some strains may become pathogenic. This study was therefore undertaken to detect coliform bacteria in ostrich faeces and to test their antibiotic profile and sensitivity to enterocins. Faeces (n=54, 18 mixture samples from 3 different age groups of 140 ostriches) were sampled to isolate coliform bacteria. The counts of coliform bacteria varied from 5.69 ± 2.4 log10 CFU/g to 5.73 ± 2.4 CFU/g. Pure colonies were identified using MALDI-TOF MS mass spectrometry and confirmed by phenotypization. Seventy-one strains were allotted to the speciesE. coli. Sixty-four of those 71 strains caused hemolysis. They were mostly polyresistant to antibiotics. Thirty-two poly-resistant strains ofE. coliwere sensitive to enterocins. These strains were most sensitive to Ent 9296 (26 strains). Moreover, Ent EM41 produced byE. faeciumEM41 (isolated from ostrich faeces) inhibited the growth of 20 strains, reaching activity of 100 AU/ml. Our results indicate the possibility of enterocins being used for prevention/reduction of coliforms. Of course,in vivostudies are also being processed.
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Мarchyshyna, YE, V. Melnyk y M. Yaremchuk. "Features of safe and healthy behavior of ostrich care workers". Sučasne ptahìvnictvo, n.º 5-6 (25 de junio de 2020): 18–25. http://dx.doi.org/10.31548/poultry2020.05-06.018.
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The historical aspects, significance, peculiarities of ostrich behavior and occupational safety of ostrich farm workers are analyzed. It is noted that ostrich farming began in the world in the late XIXth century. The authors study the domestic and foreign practice of stausivnytstva. Describes the significant contribution of the industry in obtaining ostrich products – leather, meat, eggs, feathers. The value of staus products in comparison with other species of animals is noted. It is emphasized that during the care, feeding and observation of ostriches it is necessary to follow the established precautions. An ostrich can kick from bottom to top with a force of 30 kg per 1 sq. km. With one blow it can easily injure the worker. It has been established that ostriches are quite aggressive during the reproductive period – they can take the employee as an opponent with all the negative consequences. It is noted that during work with adult ostriches (transfer to another place, loading into vehicles, carrying out of medical and preventive actions, etc.) for calming of a bird apply a special hook not less than 2 m long by means of which its head presses to the earth, and then put on an opaque hood on his head. Ostriches can be caught in the appropriate gutters, grabbing them by the head with a hook or hands. Experienced handlers use a number of specialized tools, including boards, hooks and limiters. Due to the risk of injury to birds or humans, ostriches should be handled by an experienced worker. It is noted that it is better to walk a bird to three workers, one holding each wing and one pushing from behind. Ostriches require a very good fence, as they can slip through or go over strung-wire stock fences. Measures to prevent injuries to workers during the care and breeding of poultry are described. It is noted that breeding ostriches is one of the most profitable businesses in agriculture.
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Yuan, Kunpeng, Dongdong Wang, Qingdong Luan, Ju Sun, Qianwen Gao, Zhiyao Jiang, Shouchun Wang et al. "Whole Genome Characterization and Genetic Evolution Analysis of a New Ostrich Parvovirus". Viruses 12, n.º 3 (19 de marzo de 2020): 334. http://dx.doi.org/10.3390/v12030334.
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Ostrich diseases characterized by paralysis have been breaking out in broad areas of China since 2015, causing major damage to the ostrich breeding industry in China. This report describes a parvovirus detected in ostriches from four different regions. The entire genomes of four parvovirus strains were sequenced following amplification by PCR, and we conducted comprehensive analysis of the ostrich parvovirus genome. Results showed that the length genomes of the parvovirus contained two open reading frames. Ostrich parvovirus (OsPV) is a branch of goose parvovirus (GPV). Genetic distance analysis revealed a close relationship between the parvovirus and goose parvovirus strains from China, with the closest being the 2016 goose parvovirus RC16 strain from Chongqing. This is the first report of a parvovirus in ostriches. However, whether OsPV is the pathogen of ostrich paralysis remains uncertain. This study contributes new information about the evolution and epidemiology of parvovirus in China, which provides a new way for the study of paralysis in ostriches.
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CHRISTAKI (Ε. ΧΡΗΣΤΑΚΗ), E. "Some principles of ostriches nutrition and their products." Journal of the Hellenic Veterinary Medical Society 52, n.º 1 (31 de enero de 2018): 18. http://dx.doi.org/10.12681/jhvms.15402.
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The ostriches have been farmed for about 150 years in South Africa. They are flightless birds but fast runners. Adults usually weigh more than 130 kg and stand up to 2.7 m tall. Domesticated ostriches reach maturity at 2-3 years old. Theirgastrointestinal tract is more similar to that of ruminants than to poultry's. The ostriches derive a lot of energy from feed fibre through the production of volatile fatty acids, in large intestine. The ostriches tend to be a credible competitor in the red meat market because of the quality of its meat (low in cholesterol and fat, high protein) .The eggs and nearly all parts, feathers, leather and meat, of the slaughtered ostrich can be used for commercial purposes.
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Faux, Cynthia y Daniel J. Field. "Distinct developmental pathways underlie independent losses of flight in ratites". Biology Letters 13, n.º 7 (julio de 2017): 20170234. http://dx.doi.org/10.1098/rsbl.2017.0234.
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Recent phylogenetic studies question the monophyly of ratites (large, flightless birds incorporating ostriches, rheas, kiwis, emus and cassowaries), suggesting their paraphyly with respect to flying tinamous (Tinamidae). Flightlessness and large body size have thus likely evolved repeatedly among ratites, and separately in ostriches ( Struthio ) and emus ( Dromaius ). Here, we test this hypothesis with data from wing developmental trajectories in ostriches, emus, tinamous and chickens. We find the rate of ostrich embryonic wing growth falls within the range of variation exhibited by flying taxa (tinamous and chickens), but that of emus is extremely slow. These results indicate flightlessness was acquired by different developmental mechanisms in the ancestors of ostriches (peramorphosis) and the emu–cassowary clade (paedomorphosis), and corroborate the hypothesis that flight loss has evolved repeatedly among ratites.
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Bushra Nisar Khan, Iqra Islam, Nisar Ahmed, Muhammad Oneeb, Muhammad Azhar, Kiran Saleem y Muhammad Rizwan Khan. "Prevalence and Management of Endoparasitic Worm load in Ostriches of Different Captive Conditions Housed in Punjab, Pakistan". Lahore Garrison University Journal of Life Sciences 7, n.º 02 (26 de junio de 2023): 197–98. http://dx.doi.org/10.54692/lgujls.2023.0702260.
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Ostrich farming has attained a status of a fast-growing agribusiness in the livestock industry due to the wide range of associated benefits attached to it. This study was designed to assess the prevalence of endoparasites in this economically important bird as well as their treatment to provide better guidelines for successful ostrich farming. The study involved 385 feacal samples of ostriches taken from 55 commercial farms and captive sites Punjab during the period of January 2020 to December 2020. The relevant data and samples were collected from 15 districts of Punjab. Feacal samples were tested against gastrointestinal worm load by using floatation and sedimentation techniques. Ostriches of 11 commercial farms and Lahore Zoo, Jallo Wildlife Park Lahore, UVAS Ostrich farm Pattoki and Bahawalnagar Wildlife Park were found to harbor protozoan parasites such as Eimeria spp. Balantidium coli, and Amoeboid cyst. It was noteworthy that the use of herbal dewormers showed much better results than chemical anthelmintics. Similarly, those wildlife parks where ostriches were given a natural environment showed negative results for endoparasites. At some farms combination of chemical and herbal anthelmintics was also used. The absence of a reliable nutritional management system caused the mortality of ostriches at 40 farms due to gastric problems and choking. The mortality rate at the age of 2-4 months was 73% while mortality of adult birds from 1-7 years was 27%. Among selected farms, 50% of ostriches were facing lameness, leg deformities, and retarded growth due to improper space, a congested environment, and poor feeding systems. Lastly, more research is needed to make this agribusiness flourished.
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Shameeva, U. G., G. K. Dzhanabekova, M. M. Zhylkyshybaeva, M. Sh Erezhepova y Zh M. Otebaev. "Dynamics of oval production of the black african ostrich, incubation indicators". Kazakhstan zoological bulletin 1, n.º 1-2 (2020): 56–63. http://dx.doi.org/10.54944/kzbes177lv11.
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The egg-laying cycle of the black African ostrich usually lasts up to 240 days. They change dynamically from time to time. It is influenced by various factors. This is directly related to the peculiarities of feeding, growing, keeping. During the study, the ostriches were divided into three groups, and an ostrich feed additive was added to their feed. In the course of the study, the influence of the feed additive on the dynamics and egg production was determined. As a result, the dynamics of egg production in ostriches that received the feed additive increased by 23% and the incubation rate was 60%.
Tesis sobre el tema "Ostriches"
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Bezuidenhout, Cornelius Carlos. "Studies of the population structure and generic diversity of domesticated and "wild" ostriches (Struthio camelus)". Thesis, Rhodes University, 2000. http://hdl.handle.net/10962/d1003966.
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DNA sequencing and restriction fragment length polymorphism analysis (RFLP) of polymerase chain reaction (PCR) amplified mitochondrial DNA fragments, and random amplified polymorphic DNA sequence (RAPD) analysis were techniques evaluated in this study for applicability in the investigation various aspects of genetic diversity within the ostrich (Struthio camelus). The genetic aspects that were investigated were (i) relationships between ostrich subspecies, (ii) genetic variability between and within domesticated populations of southern African ostriches (Struthio camelus australis), (iii) linking egg production in domesticated ostriches to RAPD profiles, and (iv) determining the zygosity of twin ostriches. In the first part of this study DNA sequencing and the polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP) methods were evaluated for resolving genetic differences in the small mtDNA fragments ofthe ostrich. DNA sequencing ofPCR amplified 450 bp 12S rRNA gene fragments of representatives from the southern African population ostrich (S.c. australis) did not reveal any differences between the populatiohs from different geographical areas, representing ostrich lineages with different breeding histories. The PCRRFLP analysis ofmtDNA fragments (450 bp 12S rRNA gene fragment and 550 bp D-loop region) also did not reveal any genetic variability between the domesticated s.,c. australis populations included in this study. PCR-RFLP analysis of a 450 bp 12S rRNA gene fragment, however, showed differences between the subspecies s.c. australis and s.c. molybdophanes. The proportion of shared fragments (F) between these two subspecies was 0.286 and nucleotide sequence divergence estimated at 8.9 %. Divergence time between these two subspecies was estimated at 4.5 million years ago. The data presented from this study are comparable to the data from a previous study in which the entire mitochondrial genome and a larger number of restriction enzymes were used. The PCR-RFLP method thus demonstrated its usefulness for genetic studies of ostriches at thesubspecies level. The sequences used in this study could not reveal any markers that were useful for genetic studies of ostriches at the population level. In the second part of the study the RAPD method was evaluated for application in the genetic studies of ostriches. RAPD profiles, based on three RAPD primers, revealed differences between three subspecies of ostriches and indicated relationships between these subspecies that are consistent with observations from other studies. The numerical analysis of pooled and individual primer data demonstrated that the subspecies s.c. australis is more closely related to s.c. massaicus than to s.c. molybdophanes. RAPD marker differences between s.c. molybdophanes on the one hand, and s.c. massaicus and s.c. australis on the other is also consistent with observations from studies that proposed separate specie~ status for s.c. molybdophanes. RAPD analysis by five primers revealed geographic variation between s.c. australis populations. The clustering patterns observed in the dendrograms and Neighbour Joining Trees generated by computer programs showed trends of separating ostric1;t populations into geographical groups, possibly reflecting their different breeding histories. In the RAPD profiles of the inbred population, band-sharing was generally greater than in the outbreeding group. RAPD analysis thus showed that it may be a useful method in the population studies of domesticated S. c. australis. RAPDs also generated data that grouped ostriches according to trends in egg production capabilities. Analysis ofRAPD profiles by computer software showed a Neighbour Joining Tree and a dendrogram that predominantly grouped ostriches into clusters associated with either good or poor egg production. Evidence supporting the suitability of RAPDs as a tool in breeding programmes of ostriches was thus provided by this study. RAPDs also provided data, demonstrating that two sets of ostrich twins were non-identical twins. It was demonstrated by this study that RAPDs analysis may be a useful technique for applying to (1) systematic (2) population (3) breeding and (4) twin studies of ostriches (Struthio camelus).
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Kimaro, Wahabu Hamisi. "An immunohistochemical and ultrastructural study of the ovary of the immature ostrich (Struthio camelus)". Diss., Connect to this title online, 2005. http://upetd.up.ac.za/thesis/available/etd-04032007-165936/.
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Gough, Fionnuala Mary. "Irish ostriches, embryos and stem cells". Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/irish-ostriches-embryos-and-stem-cells(3a3aef52-1ab5-43d6-9bf8-b29ce28b5e32).html.
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Human embryonic stem cell research would seem to offer the prospect of developing a greater understanding of, and potential therapies for, common degenerative diseases such as diabetes mellitus, Alzheimer’s and Parkinson’s disease. Despite the fact that some Irish institutions engage in such research, Ireland is one of the few countries in Europe which has failed to produce any relevant regulatory framework or legislation. This is largely because embryo research and its regulation remain mired in conflicting socio-political values and interests, despite the fact that the in vitro human embryo is not afforded any legal protection under the Irish Constitution. This thesis seeks to examine the current Irish legal lacuna in relation to embryos and embryonic stem cell research. The first of the three papers making up the core of this thesis reviews the background to the moral, legal and social factors that have contributed to the extant Irish position. A description of the divergent policies enacted in other jurisdictions is also given to outline possible policy options which may be considered by Ireland in the future. The views of relevant stakeholders on the impact of the regulatory lacuna are explored in the second paper through a series of semi-structured interviews. These interviews highlight a surprising level of consensus on the need for the Irish legislature to act and introduce regulations to provide certainty, in one way or the other, in this area of scientific innovation. A procedural mechanism is proposed in the third paper which could allow the development of policy and concomitant regulation in Ireland in this area. It is hoped that the procedural process and resultant framework would be sufficiently inclusive as to be acceptable to the majority of people in Irish society. In conclusion, it is argued that it is undesirable that a modern pluralist democracy (as Ireland aspires to be) should regard legislative inertia and non-regulation as the preferred method of dealing with morally challenging scientific endeavour. Instead, appropriate procedural mechanism should be utilised to allow for the development of apposite policies.
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Viviers, Swys Francois. "Effect of dietary energy and protein on the production parameters of slaughter ostriches (Struthio camelus var. domesticus)". Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/98065.
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Thesis (MSc)--Stellenbosch University, 2015.ENGLISH ABSTRACT: When modern man assumed the responsibility of domesticating animals for his own purposes, he directly accepted the responsibility associated with feeding and caring for them. Considering intensive production systems, nutrition is one of the most important aspects in maintaining healthy livestock as well as ensuring profitability is achieved. This is due to the fact that the feeding of the livestock is often the most expensive overhead cost encountered. In ostrich production systems, nutrition costs total an estimated 70 – 80% of the costs associated with rearing the birds from chick to slaughter. When dissecting the typical composition of these ostrich diets, it becomes evident energy and protein are two of the most important, and abundant, nutrients found. Therefore, this study was conducted to investigate the effects of different concentrations of protein and energy in the diets of slaughter ostriches, on their production parameters. In the first study (Chapter 3), five diets with different protein concentrations were formulated across the four feeding phases of slaughter ostriches (pre-starter, starter, grower and finisher). Three replications per treatment were conducted resulting in 15 camps of ostriches. Significant differences (P < 0.05) were found in the live weights of the birds at the end of each feeding phase except the finisher phase. In terms of the production parameters, differences (P < 0.05) were found for the dry matter intake (DMI), average daily gain (ADG) and the feed conversion ratio (FCR). Results indicated that the birds on the middle diet (control) and on the diets containing proportionally higher protein concentrations, although not different from each other, consistently outperformed those on diets containing lower concentrations of protein. These trends were also evident when comparing the cold carcass and thigh weights of the treatment birds post-slaughter. Therefore, from a financial standpoint, it could be concluded that increasing the protein content of the diets beyond that level currently used in industry (control) is not sensible. The second study (Chapter 4) was an evaluation on the primary products harvested from the birds utilized in the first study, namely the feathers, skin and meat. The aim of the investigation was to determine if the dietary protein concentrations had any effect on these products. No differences (P > 0.05) were observed across the feather yields or classes measured, except for the ‘tail feathers’, where the birds fed the lowest protein levels in their diets yielded the fewest. Differences (P < 0.05) were however found in selected skin parameters measured. Decreased dietary protein resulted in smaller wet skin size, smaller sizes of the feather nodules, as well as smaller crust size after the tanning process was completed. However, this had no impact (P > 0.05) on the skin grades achieved. Hence it became clear that dietary protein has an impact on the skin size achieved, which did not translate into differences in skin quality. Similarly, it did not affect the feather yields or quality. Energy is the most important nutrient in livestock diets as it is the first limiting nutrient influencing intake. Therefore, in the third study (Chapter 5), treatments in the form of five different levels of energy in the diets of ostriches, were investigated. Structurally, the layout was similar to the first study with three replications per treatment yielding 15 camps of ostriches. Significant differences (P < 0.05) were found between the live weights of the birds after the pre-starter phase, but not overall after the completion of the trial. The middle diet (diet 3) containing 14.5 MJ ME/kg displayed the highest gains per day of 216.0 ± 8.08 g per chick. The results of the growth were mirrored in the production parameters (DMI, ADG, FCR), where no differences (P > 0.05) were found for the rest of the feeding phases. In a follow up investigation of the effects of dietary, this chapter focused on the impact these different energy levels (Chapter 5) had on the primary products harvested after slaughter (Chapter 6). In particular, the feather yield and quality, skin yield and selected quality parameters, as well as the chemical composition of the meat was studied. No differences were found (P > 0.05) across any of the feather yields or classes measured. Concerning the skin yields and quality, similar results were found with no differences (P > 0.05) between the crust sizes or grades. With regards to the proximate composition of the meat, no major effect (P > 0.05) was found as a result of the treatment diets. Therefore, dietary energy content exhibited little influence over the feather, skin and meat parameters measured in this study.
AFRIKAANSE OPSOMMING: Die oomblik toe die nuwerwetse mens die verantwoordelikheid aanvaar het vir die mak maak van diere vir sy eie gebruik, het hy direk die verantwoordelikheid aanvaar wat geassosieer word met hul voeding en versorging. Met inagneming van intensiewe produksiestelsels is voeding een van die belangrikste aspekte in die handhawing van gesonde vee asook om winsgewendheid te verseker. Dit is as gevolg van die feit dat die voeding van diere dikwels die grootste oorhoofse uitgawe is. In volstruisproduksiestelsels bereik die voedingskostes ‘n totale geskatte hoeveelheid van 70 – 80% van die kostes wat geassosieer word met die grootmaak van die voëls vanaf kuiken tot slagvoël. Wanneer die tipiese samestelling van hierdie volstruisdiëte ontleed word, is dit duidelik dat energie en proteïene twee van die mees belangrike en volopste voedingstowwe is wat gevind word. Hierdie studie was dus onderneem om die effek van verskillende konsentrasies proteïene en energie in die diëte van slagvoëls en hulle produksieparameters te ondersoek. Vir die eerste studie (Hoofstuk 3) is vyf diëte met verskillende proteïenkonsentrasies geformuleer vir die vier voedingsfases van slagvolstruise (voor-aanvangs, aanvangs, groei en afronding). Drie herhalings per behandeling is gebruik wat 15 volstruiskampe tot gevolg gehad het. Betekenisvolle verskille (P < 0.05) in die lewende gewig van die voëls is aan die einde van elke voedingsfase gevind, behalwe vir die afrondingsfase. In terme van die produksieparameters is verskille (P < 0.05) gevind vir die droë materiaalinname (DMI), gemiddelde daaglikse toename (GDT) en die voeromsetverhouding (VOV). Resultate het getoon dat voëls wat die middelste dieet (kontrole) en diëte wat proporsioneel hoër proteïenkonsentrasies bevat het, alhoewel hulle nie van mekaar verskil nie, konsekwent beter presteer het as die wat diëte met laer proteïenkonsentrasies ontvang het. Hierdie tendense is ook waargeneem toe die koue karkas- en dygewigte van die eksperimentele voëls na-doods vergelyk is. Vanuit ‘n finansiële oogpunt kan daar dus tot die gevolgtrekking gekom word dat dit nie sinvol sal wees om die proteïeninhoud van volstruisdiëte te verhoog bo die vlak wat tans in die industrie (kontrole) gebruik word nie. Tydens die tweede studie (Hoofstuk 4) is die primêre produkte (vere, velle en vleis) wat vanaf die volstruise in die eerste studie geoes is, geëvalueer. Die doel van hierdie studie was om te bepaal of die verskillende proteïenkonsentrasies in die dieet enige effek op hierdie produkte het. Geen verskille (P > 0.05) is by die veeropbrengste of die verskillende veertipes wat gemeet is, waargeneem nie, behalwe vir die stertvere, waar die voëls wat die laagste proteïenvlakke in hulle diëte ontvang het, die laagste opbrengs gelewer het. Verskille (P < 0.05) is egter gevind in die geselekteerde velparameters wat gemeet is. ‘n Vermindering in die proteïenkonsentrasie het ‘n kleiner nat velgrootte tot gevolg gehad, asook ‘n afname in knoppiegrootte nadat die looiproses voltooi is. Hierdie waarneming het egter geen invloed (P > 0.05) op die gradering van die velle gehad nie. Dit het dus duidelik na vore gekom dat die dieetproteïen wel die velgrootte wat bereik is, beïnvloed het, maar nie tot verskille in velkwaliteit gelei het nie. Veeropbrengs en –kwaliteit is ook nie deur die dieetproteïen beïnvloed nie. Energie is die eerste beperkende voedingskomponent wat voerinname bepaal. Gegewe die groot invloed wat dit op voerinname het, is dit dus die mees belangrike komponent in die dieet van vee. Vandaar dan die derde studie (Hoofstuk 5) waar die behandelings in die vorm van vyf verskillende energievlakke in die diëte van volstruise ondersoek is. Die struktuur en uitleg van die studie was soortgelyk aan die eerste studie met drie herhalings per behandeling wat 15 volstruiskampe tot gevolg gehad het. Betekenisvolle verskille (P < 0.05) is gevind tussen die lewende gewigte van die voëls na die voor-aanvangsfase, maar nie nadat die hele proefneming voltooi is nie. Die middelste dieet (dieet 3) wat 14.5 MJ ME/kg bevat het, het die hoogste toename per dag van 216.0 ± 8.08 g per kuiken opgelewer. Groeiresultate is weerspieël in die produksieparameters (DMI, GDT, VOV), waar geen verskille (P > 0.05) in die res van die voedingsfases gevind is nie. Tydens ‘n opvolgondersoek rakende die effek van dieet, het hierdie hoofstuk gefokus op die impak wat die verskillende energievlakke (Hoofstuk 5) op die primêre produkte wat na-doods geoes is. Daar is in besonder na die vere-opbrengs en –kwaliteit, velgrootte en geselekteerde kwaliteitparameters, asook die chemiese samestelling van die vleis gekyk. Geen verskille (P > 0.05) is by die veeropbrengste of die verskillende veertipes wat gemeet is, gevind nie. Met betrekking tot die velgroottes en -kwaliteit, is soortgelyke resultate gevind met geen verskille (P > 0.05) tussen die knoppiegrootte en –gradering nie. Met verwysing na die proksimale samestelling van die vleis is geen betekenisvolle effek (P > 0.05) as gevolg van die eksperimentele diëte waargeneem nie. Die inhoud van die dieetenergie het dus ‘n klein invloed op die vere-, vel- en vleisparameters wat in hierdie studie geëvalueer is, gehad.
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Brand, Zanell. "The effect of energy and protein nutritional levels on production of breeding ostriches". Thesis, Rhodes University, 2002. http://hdl.handle.net/10962/d1006312.
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Adequate and appropriate nutrition is essential for the production of high quality commercially farmed animal species. Although South Africa has had a well-established ostrich industry for over a century, little information on ostrich nutrition, in particular the specific nutritional requirements at different stages of production, is available. The industry has consequently relied heavily on data derived from poultry and pigs, but this has often proved to be unsatisfactory for ostriches and has resulted in serious nutritional-related problems. Recent studies on the metabolisable energy of specific components of diet formulations and balanced diets have indicated that ostriches have enhanced digestibility compared with poultry and pigs. At the same time, in the present economic climate, it is necessary to find cost-effective diets for breeding birds without compromising egg and chick production. This study primarily assessed the effect of different dietary protein and energy levels on production parameters and body condition of breeding female and male ostriches. The energy content of the diet appears to be the main constraint to egg production and breeders on low energy diets laid fewer eggs and lost more body condition compared with breeders fed higher energy diets. A diet with 8.5 MJ/kg DM and 10% protein with well balanced amino acids appears to be sufficient for female breeders without compromising production and a diet with 7.5 MJ/kg DM and 10% protein appears suitable for breeding male ostriches. Different dietary energy and protein levels similarly had little or no effect on egg quality and composition. This study also assessed the carry-over effect of the nutritional regime in one year on the production in the following breeding season. Females fed diets as low as 7.5 MJ/kg ME in the previous breeding season produced significantly fewer eggs in the next breeding season, which resulted in lower chick production. Energy had no effect on the percentage infertile eggs or on the initial egg weight. Different levels of dietary protein had no effect on egg production, egg weight, fertility, hatchability and initial chick weight.
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Schoon, Katryn. "Effect of cottonseed oilcake meal on ostrich growth performance, meat chemical composition and sensory attributes". Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/71847.
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Thesis (MScAgric)--Stellenbosch University, 2012.ENGLISH ABSTRACT: This research study consists of three investigations with regard to ostrich (Struthio camelus var. domesticus) production, meat quality and the processing of ostrich meat into a value added meat product. The first study was conducted in order to establish whether the gradual replacement of soybean oilcake meal with cottonseed oilcake meal (CSOCM) as a protein source in the diet of slaughter ostriches would affect ostrich growth performance and meat quality. A total of 105 ostriches were divided into five feeding groups according to the CSOCM inclusion level: Control (0% CSOCM), 3%, 6%, 9% and 12% CSOCM, and fed with experimental diets from 6 to 13 months of age. As a result of feeding CSOCM, the final live weight and the average daily gain significantly increased in the 12% CSOCM group compared to the other treatment diets. The proximate composition, cholesterol content, mineral and fatty acid profile of the meat remained unaffected. Considering all the results, CSOCM may be used as an alternative protein source to soybean oilcake meal in ostrich nutrition, resulting in decreased feed costs. Secondly, a descriptive sensory analysis, together with chemical and physical measurements, was performed to determine whether the manipulation of the fatty acid composition in the fan fillet (Iliofibularis muscle) as a result of feeding CSOCM would be detected on a sensory level. Two levels of CSOCM were investigated; 0% as a control and 9% CSOCM. No significant differences were found for the physical measurements (cooking loss (%) and shear force) as well as for the pH and proximate composition of the raw fan fillet. The Control group presented a higher (P<0.05) mono-unsaturated fatty acid (MUFA) content in the cooked fan fillet whereas the 9% CSOCM group showed a favourable increased (P<0.05) poly-unsaturated fatty acid (PUFA) content when compared to the cooked Control samples. As a result, the poly-unsaturated:saturated fatty acid (PUFA:SFA) ratio in the 9% CSOCM group was also higher (P<0.05). No differences (P>0.05) were found between the treatments for the n-6:n-3 (omega 6 to omega 3) ratio. The 9% CSOCM group had a more intense beef aroma, had a higher level of initial and sustained juiciness as well as increased tenderness (P<0.05). Inclusion of 9% CSOCM resulted in a favourable cooked ostrich fan fillet. Finally, the effect of feeding CSOCM on a processed ostrich meat product was investigated. Fan fillet (Iliofibularis muscle) from 13 month old birds receiving no cottonseed oilcake meal (Control) or 9% cottonseed oilcake meal (9% CSOCM) was used. Olive oil was used as a replacement for pork fat, and warthog (Phacochoerus africanus) meat was used to replace commercial pork meat in the production of a semi dry sausage, cabanossi. Olive oil was included at three levels (0%, 1% and 2%). Six treatments were investigated: Control 0% olive oil, Control 1% olive oil, Control 2% olive oil, 9% CSOCM 1% olive oil, 9% CSOCM 2% olive oil en 9% CSOCM 2% olive oil. The Control and 9% CSOCM ostrich meat did not differ significantly in chemical composition nor fatty acid profile. After smoking and drying the fat content in the cabanossi containing 0%, 1% and 2% olive oil averaged 7.2%, 7.45% and 8.65% respectively. Processed meat products containing less than 10% fat are classified as a low-fat meat product. Olive oil is a mono-unsaturated vegetable oil containing mainly Oleic acid (C18:1n9c), and low quantities of saturated fatty acids and polyunsaturated fatty acids. Total mono unsaturated fatty acids in the cabanossi increased from 47.0% to 73.0% of total fat, whilst total saturated fatty acids and total polyunsaturated fatty acids decreased from 40.6% to 19.9% and 11.6% to 6.6% respectively as olive oil increased from 0% to 2%. The inclusion of olive oil at 2% resulted in cabanossi with increased (P<0.05) tenderness, juiciness and cured red meat colour, all factors that appeal greatly to the consumer. Overall flavour was not adversely affected by the inclusion of olive oil. This investigation indicated that the use of CSOCM had no negative effect on the production performance of ostriches whilst a 9% CSOCM inclusion level resulted in meat that was found to be favourable by a trained sensory panel. Furthermore, the use of CSOCM as a feed component also had no negative effect on a processed product (cabanossi) derived from the meat obtained from the birds fed this feed component. The CSOCM used in this investigation had low levels of gossypol (10 to 20ppm) and more research is required on the effect of the use of CSOCM with higher levels of gossypol on the production performance of ostriches.
AFRIKAANSE OPSOMMING: Die studie het bestaan uit drie ondersoeke met betrekking tot volstruis (Struthio camelus var. domesticus) -produksie, -vleiskwaliteit en die vervaardiging van waarde-toegevoegde geprosesseerde volstruis-vleisprodukte. Die doel van die eerste studie was om vas te stel of die geleidelike vervanging van sojaboonoliekoekmeel met katoensaad-oliekoekmeel (CSOCM) as ‘n proteïenbron in die voeding van volstruise, die groeipersentasie en vleiskwaliteit van die Iliofibiularis spier (fan fillet) sal affekteer. ‘n Totaal van 105 volstruise is verdeel in vyf voedingsgroepe volgens die katoensaad oliekoekmeel insluitingsvlak: Kontrole (0% CSOCM), 3%, 6%, 9% en 12% CSOCM. Die onderskeie voedingsgroepe was van ses tot 13 maande ouderdom op die eksperimentele voere geplaas. Die resultate het aangedui dat die voëls in die 12% CSOCM behandelingsgroep ‘n betekenisvolle (P<0.05) toename in finale lewende massa asook gemiddelde daaglikse toename gehad het. Die proksimale samestelling, cholesterol-inhoud, mineraal- en vetsuursamestelling van die vleis was nie geaffekteer deur die insluiting van CSOCM nie. Die CSOCM kan dus wel as ‘n alternatiewe proteïenbron in die voeding van volstruise gebruik word. Laasgenoemde bevinding kan ook lei tot verlaagde voerkostes, aangesien CSOCM heelwat goedkoper is as sojaboon-oliekoekmeel. Die tweede deel van die studie was van ‘n chemiese asook sensoriese aard. ‘n Beskrywende sensoriese analiese is uitgevoer om vas te stel of die manipulering van die vetsuursamestelling in die volstruis fan fillet as gevolg van die CSOCM sensories waargeneem kan word. Die chemiese en fisiese eienskappe van die vleis is ook ondersoek. Twee vlakke van CSOCM inhoud is ondersoek; 0% (as kontrole) en 9% CSOCM. Geen betekenisvolle verskille is gevind vir die fisiese vleiskwaliteit (kookverliespersentasie en taaiheid), asook vir die proksimale samestelling en pH van die fan fillet nie. Die gekookte fan fillet van die Kontrole behandeling het ‘n betekenisvolle (P<0.05) toename in mono-onversadigde vetsure (MUFA) getoon en die 9% CSOCM het ‘n voordelige toename in poli-onversadigde vetsuur-inhoud (PUFA) gehad. Die poli-onversadigde tot versadigde vetsuurverhouding (PUFA:SFA) was as ‘n gevolg ook betekenisvol hoër. Geen verskille (P>0.05) is opgemerk in die omega-6 tot omega-3 poli-onversadigde vetsuurverhouding (n-6:n-3) nie. Met betrekking tot die sensoriese eienskappe het die 9% CSOCM ‘n meer opvallende beesvleis aroma, hoër vlakke van aanvanklike sappigheid en ook sagter vleis in vergelyking met die kontrole behandeling gehad (P<0.05). Insluiting van 9% CSOCM het gelei tot ‘n gekookte volstruis fan fillet van voornemende kwaliteit. Laastens is daar ondersoek ingestel op die vervanging van varkvet met olyfolie in die vervaardiging van ‘n volstruis cabanossi. Chemiese asook sensoriese analises is uitgevoer op die gedroogde en gerookte volstruis cabanossi. Vir die vervaardiging van laasgenoemde produkte is die fan fillet van 13 maande oue voëls van die Kontrole (0% CSOCM) en 9% CSOCM behandelings gebruik. Addisioneel tot die volstruisvleis is daar ook vlakvarkvleis (Phacochoerus africanus) gebruik om die kommersiële varkvleis te vervang. Olyfolie was ingesluit teen drie vlakke (0%, 1% en 2% van die totale mengsel). Ses behandelings was ondersoek: Kontrole 0% olyfolie, Kontrole 1% olyfolie, Kontrole 2% olyfolie, 9% CSOCM 1% olyfolie, 9% CSOCM 2% olyfolie en 9% CSOCM 2% olyfolie. Daar was geen verskille (P>0.05) in die chemiese en vetsuursamestellings van die Kontrole en 9% CSOCM volstruisvleis nie. Na die droging en rooksiklus was die gemiddelde vet-inhoud van die 0%, 1% en 2% olyfolie cabanossi monsters onderskeidelik 7.2%, 7.45% en 8.65%. Geprosesseerde vleisprodukte met ‘n vet-inhoud van minder as 10% word in die kommersiële vleisindustrie na lae vet vleisprodukte verwys. Olyfolie is baie ryk aan MUFA, veral Oleïensuur (C18:1n9c) en dit bevat ook lae hoeveelhede SFA en PUFA. Die totale MUFA inhoud in die cabanossi het toegeneem van 47.0% tot 73.0% terwyl die totale SFA en PUFA onderskeidelik afgeneem het van 40.6% tot 19.9% en 11.6% tot 6.6%, met ‘n olyfolie toename van 0% tot 2%. Die insluiting van olyfolie teen 2% het gelei tot ‘n sagter cabanossi wat meer sappig was met ‘n meer opvallende rooi gekuurde vleiskleur, wat almal eienskappe is wat dié produk meer aantreklik maak vir die verbruiker. Hierdie studie het aangedui dat CSOCM geen negatiewe effek gehad het op die produksie van volstruise nie. Volstruisvleis van die behandelingsgroep wat CSOCM teen 9% van die dieet ontvang het, het wel vleis geproduseer wat as aanvaarbaar aanskou was deur ‘n opgeleide sensoriese paneel. Die gebruik van CSOCM as ‘n voerbestandeel het ook geen negatiewe effek gehad op ‘n geprosesseerde produk (cabanossi) gemaak van die volstruisvleis nie. Die CSOCM wat in die huidige studie gebruik is, het baie lae vlakke van gossypol (10 – 20dpm) gehad en verdere ondersoek is noodsaaklik om die effek van CSOCM met hoër vlakke van gossypol op die produksie van volstruise te bevestig.
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Janse, Van Vuuren Maryke. "Faktore wat die oorlewing van volstruiskuikens (Struthio Camelus) verhoog". Thesis, Nelson Mandela Metropolitan University, 2008. http://hdl.handle.net/10948/848.
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Hierdie verhandeling is ‘n samestelling van verskeie studies, elk opgeskryf in die formaat en styl soos vereis deur die Suid-Afrikaanse Vereeniging vir Diereproduksie (South African Society of Animal Science). Hoofstuk 1 is ‘n literatuurstudie bestaande uit ‘n algemene inleiding wat agtergrond oor die studie verskaf en sluit die probleemstelling in, naamlik die swak oorlewing van volstruiskuikens wat onder kunsmatige toestande grootgemaak word. Hoofstukke 2, 3, 4 en 5 bestaan uit die eerste vier studies, waartydens sekere bestuurs-aspekte, wat moontlik oorlewing van volstruiskuikens kan verbeter (nl: populasiedigtheid, tipe vloer-oppervlak, die aanwending van broeipare en die aanwending van peetouers), ondersoek is. Hoofstukke 6, 7, 8 & 9 handel oor studies wat gerig is om voeding meer aanloklik te maak vir volstruiskuikens teneinde voedselinname te stimuleer en sodoende produksie en oorlewing te verbeter (nl: verskaffing van groenvoer, geur van voer, kleur van voer en beligting van voer). Die laaste hoofstuk bestaan uit ‘n algemene gevolgtrekking en aanbevelings. Alhoewel daar gepoog is om herhaling in hoofstukke te beperk, was dit onmoontlik om herhaling van sekere gedeeltes van hoofstukke te voorkom.
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Carstens, Petrus Daniel. "Studies to develop a mathematical optimisation model to describe the effect of nutrition on the growth of ostriches (Struthio camelus var. domesticus)". Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/85639.
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Thesis (MScAgric)--Stellenbosch University, 2013.ENGLISH ABSTRACT: The first study (Chapter 3) evaluated the growth response of ostrich chicks on diets containing three different levels of protein and amino acids. Linear and nonlinear models were fitted to the data and compared by using Akaike’s information criterion (AIC). The linear polynomial of the third degree had the lowest AIC value for all three treatments thus making it the most suitable model for the data. Significant differences were found between treatments for growth data. The results from this study can aid in describing the growth of ostriches subjected to assumed optimum feeding conditions. In the second study (Chapter 4), a range of diets was formulated for the five growth stages of ostriches (pre-starter, starter, grower, finisher and maintenance) according to their nutrient requirements. The diets were diluted with wheat straw. Three dilution levels (0%, 10% and 20%) were used for the pre-starter and starter phases, five dilution levels (0%, 15%, 30%, 45% and 60%) were used for the grower and the finisher phases, and five dilution levels (0%, 20%, 40%, 60% and 80%) were used for the maintenance phase. Weekly intake data were collected throughout each phase. Feed bulk restricted intake by 21% and 52% at the 10% and 20% dilution level, respectively (P < 0.05) in the pre-starter phase, whereas intake was not restricted during the starter phase(P > 0.05). Intake was constrained by 39% and 42% at the 45% and 60% dilution levels in the grower phase, respectively (P < 0.05), and by 17% and 39% at the 45% and 60% dilution levels (P < 0.05) in the finisher phase, respectively. Feed bulk restricted intake by 60% and 69% for the 60% and 80% dilution levels (P < 0.05), respectively, in the maintenance phase. Defining the bulk density that will constrain feed intake, as established in this study, will aid in least-cost feed formulations, feed intake modelling and growth predictions. In the third study (Chapter 5) the effect of three different dietary protein (with a specific associated amino acid content) concentrations on certain production parameters in growing ostriches were investigated. Significant differences were found for the final live weight of birds, cold carcass weight, thigh weight as well as for most of the weighed muscles at slaughter (350 days old). Concerning the growth and feed related parameters, only average daily gain (ADG) was influenced by dietary treatment (P < 0.05). Results indicated that birds on the diet with the medium protein performed optimally. One exception is the starter phase (26 – 47 kg) where chicks on the high protein diet outperformed those on the medium protein diet. In the fourth study (Chapter 6) the effects of different dietary energy concentrations on ostrich production parameters were examined in two different trials. The first trial included measurements from the pre-starter phase through the starter phase until the grower phase. The second trial was based on the finisher phase per se. Overall dietary levels provided in the pre-starter, starter and grower phases indicated better growth, FCR, skin size and grade, thigh weight, live weight, and carcass weight for the birds fed the medium energy diet. Dietary energy levels provided during the finisher phase indicated that the energy level above the medium level used improved growth rate and tanned skin size. The gender of the birds influenced carcass weight, growth rate, and certain feather parameters (P < 0.05). In the fifth study (Chapter 7) the effect of feather clipping at six to eight months of age on the production parameters of ostrich chicks were investigated. The study was conducted in three different trials. In each of the trials the feathers of half the amount of birds were clipped at six to eight months of age. Significant differences (P < 0.05) were found for the feed conversion ratio (FCR), the average daily gain (ADG) and for the quantity of valuable feathers. Results indicated that the growth rate and FCR was better for the birds which had their feathers clipped at six to eight months of age. Results also showed that the quantity of feathers with commercial value were significantly higher for the clipped group. This study showed that there may be an advantage for ostrich producers concerning the harvesting of feathers at six to eight months of age. The work in this thesis is a follow up on the framework set by Kritzinger (2011) and is part of the same project. Most of the results obtained in these studies will be incorporated in to the mathematical optimisation model of Gous and Brand (2008) for more accurate predictions concerning feed intake and other production parameters that may lower feeding costs.
AFRIKAANSE OPSOMMING: Die eerste studie (Hoofstuk 3) evalueer die groei van volstruiskuikens op diëte met drie verskillende vlakke van proteïene en aminosure. Liniêre en nie-liniêre regressiemodelle is op die data gepas en met Akaike se inligting kriterium (AIC) vergelyk. Die liniêre polinoom van die derde graad het die laagste AIC waarde vir al drie behandelings gehad. Daarom is die voorspellings van hierdie model gebruik om die groeidata te interpreteer. Beduidende verskille tussen behandelings vir groeidata (P < 0.05) is gevind. Die resultate van hierdie studie kan help met die beskrywing van die groei van volstruise, onderworpe aan aangeneemde optimale voedingsbehoeftes. In die tweede studie (Hoofstuk 4) is 'n verskeidenheid diëte geformuleer vir die vyf groeistadiums van volstruise (voor-aanvangs, aanvangs, groei, afronding en onderhoud) volgens hul voedingsbehoeftes. Die diëte is verdun met koringstrooi. Drie verdunningsvlakke (0%, 10% en 20%) is gebruik vir die voor-aanvangs- en aanvangsfase, vyf verdunningvlakke (0%, 15%, 30%, 45% en 60%) is gebruik vir die groei- en die afrondingsfase en vyf verdunningsvlakke (0%, 20%, 40%, 60% en 80%) is gebruik vir die onderhoudsfase. Weeklikse inname-data is ingesamel gedurende elke fase. In die voor-aanvangsfase het voerlywigheid (verhoging van ruvesel) inname beperk met 21% en 52% vir die 10% en 20% verdunningsvlakke (P < 0.05) onderskeidelik, terwyl inname nie beperk is gedurende die aanvangsfase nie (P > 0.05). Inname is beperk met 39% en 42% op die 45% en 60% verdunningsvlakke in die groeifase (P < 0.05) onderskeidelik, en met 17% en 39% op die 45% en 60% verdunningsvlakke in die afrondingsfase (P < 0.05), onderskeidelik. Voerdigtheid het inname beperk met 60% en 69% vir die 60% en 80% verdunningsvlakke, onderskeidelik, in die onderhoudsfase (P < 0.05). Die definiëring van die digtheid of ruvoerinhoud van voer wat inname beperk, soos in die studie bepaal, sal help met die optimering van voerformulasies, voerinname-modellering en groeivoorspellings. In die derde studie (Hoofstuk 5) is die effek van drie verskillende dieëtproteïenkonsentrasies (met 'n spesifieke gepaardgaande aminosuurinhoud) op sekere produksieparameters in die groei van volstruise ondersoek. Beduidende verskille is gevind vir die finale lewende gewig, koue karkasmassa, boudgewig sowel as vir die meeste van die geweegde spiere van voëls op slagouderdom (350 dae oud). Met betrekking tot die groei en voedingsverwante parameters, is slegs die gemiddelde daaglikse toename (GDT) beïnvloed deur die dieet (P < 0.05). Resultate het aangedui dat voëls op die medium-proteïendieet optimaal presteer. Een uitsondering is die aanvangsfase (26 – 47 kg), waar kuikens op die hoë-proteïendieet beter gevaar het as die voëls wat die medium-proteïendieet ontvang het. In die vierde studie (Hoofstuk 6) is die invloed van verskillende dieet-energiekonsentrasies op volstruis-produksieparameters in twee verskillende proewe ondersoek. Die eerste proef het gestrek vanaf die voor-aanvangsfase, deur die aanvangsfase tot en met die einde van die groeifase. Die tweede proef is gedoen vir die afrondingsfase. In die voor-aanvangs-, aanvangs- en groeifase is beter groei, voeromsetverhouding (VOV), velgrootte en -graad, boudgewig, lewende gewig en karkasgewig verkry vir die voëls wat die standaard-energie dieet ontvang het (P < 0.05). Dieet-energievlakke wat tydens die afrondingsfase fase verskaf is, het aangedui dat die energievlak bo die medium-vlak verbeterde groeitempo en gelooide velgrootte tot gevolg het (P < 0.05). Die geslag van die voëls het ’n invloed gehad op karkasgewig, groei, en sekere veerparameters. In die vyfde studie (Hoofstuk 7) is die effek van die knip van vere, op die ouderdom van ses tot agt maande, op die produksieparameters van volstruiskuikens ondersoek. Die studie is uitgevoer in drie verskillende proewe. In elk van die proewe is die vere van die helfte van die hoeveelheid voëls geknip op ses tot agt maande ouderdom. Beduidende verskille is gevind vir die VOV, die gemiddelde daaglikse toename (GDT) en vir die hoeveelheid waardevolle vere (P < 0.05). Die groeitempo en VOV was beter vir die voëls waarvan die vere op ses tot agt maande ouderdom geknip is (P < 0.05). Resultate het ook getoon dat die hoeveelheid waardevolle vere aansienlik hoër was vir die groep waarvan die vere op ses tot agt maande ouderdom geknip is (P < 0.05). Hierdie studie het getoon dat daar 'n voordeel mag wees vir volstruisprodusente indien vere geknip word op die ouderdom van ses tot agt maande. Die werk in hierdie tesis volg op die raamwerk van Kritzinger (2011) en was deel van dieselfde projek. Die meeste van die resultate wat verkry is in die studies sal in die wiskundige optimeringsmodel van Gous en Brand (2008) geïnkorporeer word vir meer akkurate voorspellings van voerinname en produksieparameters wat die voerkostes kan verlaag.
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Bonato, Maud. "Mate choice and immunocompetence in ostriches (Struthio camelus)". Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/1257.
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Thesis (PhD (Botany and Zoology))—University of Stellenbosch, 2009.Females of many bird species prefer to mate with males exhibiting elaborate ornamentation, which serves as an indicator of male quality. Such ornaments, called secondary sexual traits, could act as signals to females that males could confer direct and/or indirect genetic benefits (when offspring inherit superior genes), on offspring. In particular, it has been suggested that these signals relate to male ability to resist infections, as only high quality individuals are able to invest both in high immune defence and elaborate ornament expression. The ostrich (Struthio camelus) is the largest living bird and is a member of the family of flightless birds, the ratites. They are sexually dimorphic, males displaying black plumage, and a pink-coloured neck and bill; whereas females display dull-brown plumage (both sexes have white feathers). Little is known about the mating system of ostriches: they are promiscuous and in the wild, males and females have multiple partners. The communal nesting system of ostriches is unique in that only the major female and major male provide parental care, in the form of incubation and guarding the offspring until independence. Furthermore, a remarkable feature of cohorts is that offspring may differ greatly in size, and these size differences are likely to have a genetic basis arising from differing parental genotypic differences. As a trade-off between immune response and life-history traits has been documented in various bird species, I examined the relationships between male secondary sexual traits (and specifically colouration) and maternal investment; levels of immunocompetence in both parents and chicks; and chick growth. This study showed that females invest more at the egg stage in response to traits involved in the male courtship display: the colour of the neck, white and black body feathers, and the brightness of black feathers. As these traits, which are exposed during the courtship display as well as during male-male interactions, were related to male immune responses, I suggest that only high quality males will be able to display their condition optimally. Chicks with higher growth rates were found to have intermediate responses to stimulation of their humoral immune system with diphtheria and tetanus vaccines, suggesting that not only fitness benefits, but also costs are associated with mounting an immune response; and that variation in humoral responses and growth rates relates to how individuals trade off these costs and benefits. In addition, chick humoral responses were found to be related to the humoral response of both parents, but through different antibody responses (maternal responses to tetanus and paternal responses to diphtheria), suggesting that this component of the immune system is heritable. As the colouration of white feathers predicted chick growth rates, as well as a male’s ability to raise an antibody response, I suggest that this visual cue could serve as a signal to females of male humoral immunocompetence, therefore forming the basis of mate choice whereby females could increase the fitness of their offspring through higher growth rates.
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Lorenzen, Jan Frederik George. "The effect of lairage time and transport density on live weight losses and meat quality in slaughter ostriches". Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/71714.
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Thesis (MScAgric)--Stellenbosch University, 2012.ENGLISH ABSTRACT: Although transport and lairage of ostriches are accepted causes of production losses, these losses have not yet been quantified. Transport and lairage regulations focus on the wellbeing of the birds and, by default reduce some losses. This thesis investigated weight losses and meat quality of ostriches as a result of transport density, lairage duration and lairage feed availability (ad libitum). All birds were reared on the same farm and loaded and transported together. They were randomly divided into their respective groups on loading for the transport trial, and on offloading for the lairage trial. Bird grouping was according to density for the transport trial (4 groups, H1, H2: 0.56m2/bird and L1, L2: 0.96m2/bird) and according to time spent in lairage and feed availability for the lairage trial (n=30 birds/group; L0hr and L24hr; n=15 birds/group L48hr and L48hr ad libitum feed). Behavioural observations of the ostriches showed a tendency of the ostriches to lean against objects and to orientate towards forces exerted on it to help keep its balance. Reactions to sound fluctuations were noted, with birds reacting towards changes in sound volume during transport and lairage. Timepoint numbers were allocated for each time the birds were weighed during the trial. Time points 1, 2, 3, 4 and 5 were allocated to loading, arrival, 19 hr in lairage, 31 hr in lairage and 39 hr in lairage respectively for Trial 2. Results showed no differences (P > 0.05) in live weights or meat quality parameters between Groups H1, H2, L1 and L2 during transport. Differences (P < 0.05) were found in cumulative weight losses between L0hr and the rest of the groups for time point 1. Differences between L48hr and L48hr ad libitum were found for time point 4 for cumulative weight loss. L48hr also differed significantly between the other lairage duration groups for dressing percentages as a function of loading weight. Ad libitum feed availability had a significant effect on live body weight changes but not the meat quality parameters for the groups held for 48hr in lairage. The number of birds having bruises (≈50% per group) was similar between groups and lairage had no influence on bruising. Results seem to indicate that the evaluated transport densities had no effect on the weight loss or meat quality of ostriches. However, the results indicate that the lairage period should be studied further with specific reference to weight losses during lairage. Meat quality was unaffected by the lairage parameters reported in this thesis.
AFRIKAASE OPSOMMING: Hoewel vervoer en voorslag hou (“lairage”) aanvaar word as die oorsake van produksieverliese, is hierdie aspekte nog nie gekwantifiseer nie. Regulasies in terme van vervoer en voorslag hou fokus op die welstand van die voëls en gevolglik verminder sommige verliese met hierdie faktore. Konflik tussen boere en sekondêre produsente (abattoirs en verwerkers) oor die kostes verbonde aan hierdie gewigsverliese, is in wese ‘n oorsaak van oorbruggingsfases (vervoer). Daarom is die voorslag hou-parameters van tyd, voerbeskikbaarheid en laai digtheid ondersoek. Twee proewe is geloods; een vir vervoer en een vir voorslag aanhou. Voëls is voor hulle op vragmotors gelaai is, geweeg en op spesifieke tye daarna geweeg. Diere van die laaidigtheidsproef is ingedeel in vier groepe (H1, H2: 0.56m2/voel en L1, L2: 0.96m2/voel). Met aflaai is die eerste toets groep geslag terwyl die tweede toets groep ingedeel is volgens die tyd gespandeer en voer beskikbaarheid in voorslag aanhou (n=30 voëls/groep - Groepe L0u, L24u; n=15 voëls/groep - L48u en L48u ad libitum gevoer). Gedrag van voëls is aangeteken tydens vervoer. Finale gewig was slagpale gewig en elke tyd periode waar die voëls geweeg is, is aangeteken as ‘n tydpunt. Vleiskwaliteit analises is gedoen op die linker boud se fan filet. ‘n Standaard rak leeftyd toets is ook gedoen om kwaliteit parameters te toets oor tyd. pH is gekatorigiseer volgens groepe om moontlike verskille te beklemtoon. Gedrag is opgeteken volgens die oriëntasie en steunings gewoontes van die volstruise gedurende vervoer. Voëls probeer hulle balans te hou deur op voorwerpe en op mekaar te leun, asook om hul liggaam oriëntasie te gebruik. Reaksies tot klank veranderinge is ook opgemerk tydens vervoer en voorslag aanhou. Resultate toon geen betekenisvolle verkille tussen digtheid groepe H1, H2, L1 en L2 nie. Geen gewigsverskille is gevind tussen vervoerdigtheid groepe nie. Vleiskwaliteit-parameters is ook ondersoek en geen verskille is gevind tussen groepe nie. Resultate toon wel betekenisvolle verskille in gewigsverlies-persentasie tussen groepe vir tyd in voorslag aanhou. Groepe L48u en L48u ad libitum, het onder andere betekenisvol verskille getoon vir tydpunt 4. Betekenisvolle verskille in uitslagpersentasie as funksie van begin-gewig tussen 48 uur en die res van die groepe is ook gevind. Verdere vleiskwaliteit-parameters (drupverlies, pH, ens.) tussen groepe het geen betekenisvolle verskille getoon nie. Resultate dui aan dat voer beskikbaarheid het ‘n invloed op gewigsverskille in voorslag aanhou. Regulasies vir voorslag hou, vervoer en welstand van volstruise sal moontlik verder ondersoek moet word met spesiale klem op die nut van voorslag aanhou en die se invloed op gewigsverlies. Vleiskwaliteits-parameters is nie beïnvloed deur die aspekte ondersoek nie.
Libros sobre el tema "Ostriches"
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Volker, Janssen, ed. Ostriches. Simon's Town, South Africa: Janssen Publishers, 2007.
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Kiladze, A. B. Afrikanskiĭ straus: Rezervnyĭ potent︠s︡ial v ispolʹzovanii produktov strausovodstva. Moskva: T-vo nauch. izd. KMK, 2011.
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R, Anibal Robalino. Manual del avestruz en el Ecuador. Quito, Ecuador: Sur Editores, 2000.
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Corominas, Juan C. O$trich opportunity: A complete guide to informative, successful and profitable ostrich ranching. Editado por Fletcher Kenneth C. Fort Worth, Tex: The Summit Group, 1993.
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Hallam, M. G. The topaz introduction to practical ostrich farming. [Harare, Zimbabwe: M.G. Hallam, 1992.
Buscar texto completoCapítulos de libros sobre el tema "Ostriches"
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Broom, Donald M. "Welfare of deer, camelids and ostriches." En Broom and Fraser’s domestic animal behaviour and welfare, 369–70. 6a ed. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789249835.0035.
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Peng, Ke Mei. "Aves: Immunological Characteristics of Fowls and Ostriches". En Advances in Comparative Immunology, 793–838. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-76768-0_22.
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McNeill Alexander, R. "The Legs of Ostriches (Struthio) and Moas (Pachyornis)". En Architecture in Living Structure, 59–68. Dordrecht: Springer Netherlands, 1985. http://dx.doi.org/10.1007/978-94-009-5169-3_6.
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Malkinson, M., Y. Weisman, S. Perl y E. Ashash. "A Borna-Like Disease of Ostriches in Israel". En Borna Disease, 31–38. Berlin, Heidelberg: Springer Berlin Heidelberg, 1995. http://dx.doi.org/10.1007/978-3-642-78618-1_3.
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Graffam, Joseph. "2. “About Ostriches Coming Out of Communist China”". En Pragmatics & Beyond, 9. Amsterdam: John Benjamins Publishing Company, 1985. http://dx.doi.org/10.1075/pb.vi.6.02gra.
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Ogawa, Hiroshi, Hidehiko Uchiyama, Koji Masuda, Takeshi Sasaki, Tadao Watanabe, Toshiaki Tomizawa y Schu Kawashima. "Radioactive Contamination of Ostriches in a Potentially Permanent Evacuation Zone". En Agricultural and Forestry Reconstruction After the Great East Japan Earthquake, 203–9. Tokyo: Springer Japan, 2015. http://dx.doi.org/10.1007/978-4-431-55558-2_14.
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Pérez Orrico, Maria Luisa y Mikel Sabater González. "Ophthalmology of Palaeognathae: Ostriches, Rheas, Emu, Cassowaries, Tinamous, and Kiwis". En Wild and Exotic Animal Ophthalmology, 627–48. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-71302-7_25.
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Crosby, Faye J., Ann Pufall, Rebecca Claire Snyder, Marion O’Connell y Peg Whalen. "The Denial of Personal Disadvantage Among You, Me, and All the Other Ostriches". En Gender and Thought: Psychological Perspectives, 79–99. New York, NY: Springer New York, 1989. http://dx.doi.org/10.1007/978-1-4612-3588-0_5.
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Kadirbeyoglu, Zeynep. "In the Land of Ostriches: Developmentalism, Environmental Degradation, and Forced Migration in Turkey". En Environment, Forced Migration and Social Vulnerability, 223–34. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-12416-7_17.
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Needham, T. y L. C. Hoffman. "Chapter 8: Species destined for non-traditional meat production: 1. African game species, cervids, ostriches, crocodiles and kangaroos". En Preslaughter handling and slaughter of meat animals, 313–47. The Netherlands: Wageningen Academic Publishers, 2022. http://dx.doi.org/10.3920/978-90-8686-924-4_8.
Texto completoActas de conferencias sobre el tema "Ostriches"
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Cloete, S. W. P., A. Engelbrecht y Z. Brand. "604. Strain and age effects, as well as genetic parameters for adult traits in ostriches". En World Congress on Genetics Applied to Livestock Production. The Netherlands: Wageningen Academic Publishers, 2022. http://dx.doi.org/10.3920/978-90-8686-940-4_604.
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Taelman, Ruben, Miel Vander Sande y Ruben Verborgh. "OSTRICH". En Companion of the The Web Conference 2018. New York, New York, USA: ACM Press, 2018. http://dx.doi.org/10.1145/3184558.3186960.
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Seco, João Costa, Hugo Lourenço, Joana Parreira y Carla Ferreira. "Nested OSTRICH". En MODELS '22: ACM/IEEE 25th International Conference on Model Driven Engineering Languages and Systems. New York, NY, USA: ACM, 2022. http://dx.doi.org/10.1145/3550355.3552442.
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Houhou, Mohammad. "The Ostrich Politic". En SIGGRAPH '19: Special Interest Group on Computer Graphics and Interactive Techniques Conference. New York, NY, USA: ACM, 2019. http://dx.doi.org/10.1145/3302502.3314052.
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Houhou, Mohammed. "The ostrich politic". En SA '19: SIGGRAPH Asia 2019. New York, NY, USA: ACM, 2019. http://dx.doi.org/10.1145/3354919.3365175.
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Ismatullaev, Ilyos, Jurabek Ulugmuratov, Avaz Kenjaev, Khashim Begaliev y Fazli Akyüz. "Investigation of the Process of Soaking when Processing Ostrich Skins". En The 9th International Conference on Advanced Materials and Systems. INCDTP - Leather and Footwear Research Institute (ICPI), Bucharest, Romania, 2022. http://dx.doi.org/10.24264/icams-2022.iii.12.
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In this work, the results of a study of the process of soaking in the processing of exotic leather raw materials of ostrich skins were carried out. In order to reduce the negative impact of wastewater from the tanning industry on the environment and to accelerate the soaking process, an enzyme preparation of microbial origin Letan SE2 and a surfactant CH-22C, which meets the requirements of the European regulations REACH and ECHA, were used. When these chemicals are used in the soaking process, mucopolysaccharides and non-collagen proteins are intensively removed from the interfiber space, the moisture content in the skin tissue of the ostrich skin increases, and uniform soaking in thickness and area is ensured. Intensive and correct soaking process improves the quality of subsequent processing of the ostrich skin. The paper shows the possibility of carrying out the soaking process using environmentally friendly chemicals, the use of which allows reducing the level of technogenic impact of chemicals on the environment, which is very important for the preservation of natural objects.
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Chen, Guangrong, HuaFeng Lu, Sifan Li, Ming Ma y Sheng Guo. "A Bio-inspired Ostrich-like Biped Robot". En 2021 China Automation Congress (CAC). IEEE, 2021. http://dx.doi.org/10.1109/cac53003.2021.9728521.
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Eriksson, Benjamin, Amanda Stjerna, Riccardo De Masellis, Philipp Rüemmer y Andrei Sabelfeld. "Black Ostrich: Web Application Scanning with String Solvers". En CCS '23: ACM SIGSAC Conference on Computer and Communications Security. New York, NY, USA: ACM, 2023. http://dx.doi.org/10.1145/3576915.3616582.
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Zhang, Lifeng, Yanling Cui y Keqin Li. "Ostrich: An optimistic distributed power control scheme for VANETs". En 2014 IEEE Wireless Communications and Networking Conference (WCNC). IEEE, 2014. http://dx.doi.org/10.1109/wcnc.2014.6952648.
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YuRong Yang y YiBao Jiang. "Anatomy and Histology of cloaca in African ostrich (Struthio camelus)". En 2011 International Conference on Remote Sensing, Environment and Transportation Engineering (RSETE). IEEE, 2011. http://dx.doi.org/10.1109/rsete.2011.5964023.
Texto completoInformes sobre el tema "Ostriches"
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Olafsson, Arna y Michaela Pagel. The Ostrich in Us: Selective Attention to Financial Accounts, Income, Spending, and Liquidity. Cambridge, MA: National Bureau of Economic Research, octubre de 2017. http://dx.doi.org/10.3386/w23945.
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